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Is it rich or oil burning ?
In my experience, rich gives a uniform thickness colour ...

Rusty by nature

I don't know, I'm no expert really. What's the difference?

It was also popping out of the carb when I tried to start it yesterday, I've checked the fuel pressure and it's just over 2.5psi, so isn't forcing it's way out of the car. It's running megajolt on a Tom Fenton machined bracked and pulley, with a max advance of 28/30, so i'm pretty sure the timing isnt out.

any ideas?

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Backfire through the carb is lean. Backfire out the zorst is rich. Black smoke out the zorst is rich, blue is oil white is water.

In the 13's at last!.. Just

Hard to tell from the pics, but are the plugs oily or sooty?

You can test if its the guides/seals by jacking the front of the car up while its running, but from what you describe (smoking under load) it sounds like its more likely to be rings.

In the 13's at last!.. Just

Well it's definitely blue smoke out the back, it looks like an effing stunt plane...

So if it's running lean and popping out of the carb, how come the plugs are black? Or can burning oil do that to them? There's also about half a mil of carbon soot in tail pipe.

The only thing I've yet to look at is valve clearances. failing that I think i'll have to take the head off to have a look at bore walls and valve guides etc?

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Valve stem seals?

Is there a way of telling if they are the problem, without taking the head off and the springs off?

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Remove your rocker cover and check if any have lifted up of the guides.

Took the rocker cover off, found that it was full of mayo:

I could see seals on three of the inlets, couldn't see one on the fourth but doesn't mean it isn't there as the double valve springs and oil obscure the view. Tappet clearences are okay as well.

So I cleaned the plugs and the carb, got some new fuel and put it all back together, it does run but tends to hunt at idle now and reving it will cause popping out of the carb.

So this means it's running lean? So it needs a different needle? But what could have caused it to start doing it suddenly?

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

Looking at that your head gasket has gone.

Hence the blue smoke...

Carb could be crudded up with shit from the tank.

That rocker cover looks normal.

In the 13's at last!.. Just

I thought head gasket when I saw that, same thing happened last time I had a head gasket go.

I had the carb off and gave it a clean yesterday, so I dont think that's it.

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Edited by jonny f on 13th Mar, 2013.

What oil are you using? I've seen halfaruds classic oil leave spunk in your rocker top like that.

What oil are you using? I've seen halfaruds classic oil leave spunk in your rocker top like that.

that amount of mayo could easily just be from the damp in the air at this time of the year

13.95 1/4 mile on a 2.95 fd. Carnt be that hard to beat!

The head has had a light skim yes, and I don't think I was retorqued?

I'm using comma classic 20/50, the stuff that comes in metal cans

http://www.turbominis.co.uk/forums/index.p...tid=469104&fr=0

Has the coolant level dropped?
Is the timing alright?
I had backfiring out the carb and a sooty exhaust when I burnt an exhaust valve, it must of been getting so hot it was igniting the mixture on the intake stroke.
And it is possible that you are running lean and burning oil which would result in black plugs.
If you could borrow an exhaust gas thingy or colour tune or something you could take a look to see if you are running rich.

Edited by jonny f on 13th Mar, 2013.

The coolant level has dropped, but not significantly. The burnt valve sounds possible, it is a 295 head so the chances are high.

And I didn't realise that about the head, worth getting another gasket and redoing it?

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I've never found that retorquing makes the slightest bit of difference.

In the 13's at last!.. Just

Block tester will let you know...

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

Ditto what they both said ^^^

On 5th Oct, 2014 Shauna said:
What that's crazy, you go commando hahaha! How heavy is your helmet ?

Thanks guys, I'll get on to some local garages to see if they can do it, failing that there's always the AA man...

Isn't there a way of testing piston rings by doing 2 compression tests, one normally and one with a squirt of oil?

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Normally a bit of oil in the bore will help seal the piston rings, but won't really do much for any other types of leakage, so if you have poor compression it can help narrow down the cause. But 190psi doesn't sound very low to me